Steps Toward Determination of the Size and Structure of the Broad-Line Region in Active Galactic Nuclei. XIV. Intensive Optical Spectrophotometric Observations of NGC 7469

Authors

• S.J. Collier, University of St. Andrews, St. Andrews, Scotland
• Keith Horne, University of St. Andrews, St. Andrews, Scotland
• Shai Kaspi, Tel Aviv UniversityFollow
• Hagai Netzer, Tel Aviv UniversityFollow
• Bradley M. Peterson, Ohio State UniversityFollow
• I. Wanders, University of St. Andrews, St. Andrews, Scotland
• T. Alexander, School of Physics and Astronomy and the Wise Observatory, The Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv, Israel
• R. Bertram, Ohio State University, Columbus, OH
• A. Comastri, Osservatorio Astronomico di Bologna, via Zamboni, Bologna, Italy
• C. Martin Gaskell, University of Nebraska-LincolnFollow
• Yu. F. Malkov, Crimean Astrophysical Observatory, Crimea, Ukraine
• D. Maoz, School of Physics and Astronomy and the Wise Observatory, The Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv, Israel
• M. Mignoli, Osservatorio Astronomico di Bologna, viz Zamboni, Bologna, Italy
• Richard William Pogge, Ohio State UniversityFollow
• V.I. Pronik, Crimean Astrophysical Observatory, Crimea, Ukraine
• S.G. Sergeev, Crimean Astrophysical Observatory, Crimea, Ukraine
• Stephanie A. Snedden, University of Nebraska-LincolnFollow
• G.M. Stirpe, Osservatorio Astronomico di Bologna, via Zamboni, Bologna, Italy
• N.G. Bochkarev, Sternberg Astronomical Institute, Moscow, Russia
• A.N. Burenkov, Special Astrophysical Observatory of Russian Academy of Sciences, Nyzhnij Arkhyz, Russia
• A.I. Shapovalova, Special Astrophysical Observatory of Russian Academy of Sciences Nyzhnij Arkhyz, Russia
• R.M. Wagner, Ohio State University, Columbus

Document Type

Article

Date of this Version

6-10-1998

Comments

Published in THE ASTROPHYSICAL JOURNAL, 500:162-172, 1998 June 10, 1998. Copyright The American Astronomical Society; published by University of Chicago Press. Used by permission. http://www.journals.uchicago.edu/ApJ/issues.html.

Abstract

We present results of an intensive 2 month campaign of ground-based spectrophotometric monitoring of the Seyfert 1 galaxy NGC 7469, with a temporal resolution [approximately less than]1 day. The broad Hα and Hβ emission lines respond to ~35% ultraviolet continuum variations with an amplitude of ~10% and time delays of 5.6±1.3 days and 5.4±0.8 days, respectively. We interpret this as evidence of variable Balmer line gas ~5-6 light days from the central source in this object, widely believed to be a supermassive black hole. The virial mass of the central source implied by line widths and time delays is ~10⁶-10⁷ M_◉ Concomitantly, we find evidence for wavelength-dependent continuum time delays : optical continuum variations lag those at 1315 Å by 1.0±0.3 days at 4865 Å to 1.5±0.7 days at 6962 Å. . This suggests a stratified continuum reprocessing region extending several light days from the central source, possibly an accretion disk.